Massimo returns to Renaissance Venice after years of fighting the Turks to learn that Elena, his former sweetheart, is now married to the city's tyrannical Doge. He avoids resuming this romance, despite Elena's apparent interest, because he is now falling in love with the beautiful, blonde Katarina. He also avoids becoming involved in a plot to overthrow the Doge, but after a friend is tortured and killed by the Doge's men, Massimo feels compelled to join the spreading revolt.